There are a lot of examples on log4j on the 9CBS, some written very well, but in order to consolidate knowledge, I also wrote a copy.
My requirements for log4j are not very high, there are two main purposes.
A) How to use log4j and common-logging packages in web applications;
2) How the normal Java application uses log4j and common-logging packages;
First summarize simple, how to use log4j and common-logging packages in ordinary Java applications
Proceed as follows:
1) Add log4j.jar and common-logging.jar two packages to environment variables or classpath
2) Write log4j.xml files, for example:
3) How to use in the program:
Package com.log4j.test;
Import org.apache.log4j.xml.domconfigurator;
Import org.apache.commons.logging. *;
Class configlog4j {public static void config () {Domconfigurator.configure ("config / log4j.xml");}} public class testlog4j {private log log = logfactory.getlog (Testlog4j.class);
Public Testlog4j () {configlog4j.config ();
}
Public void test1 () {log.debug ("debug test"); log.info ("info test"); log.warn ("Warn Test"); log.error ("Error Test");} public static void Main (String [] args) {testlog4j test = new testlog4j (); test.testprint1 ();
}
}
OK! This will print a message as required.
Also attached to log4j.dtd
Log4j: Configuration
|
- Appender (Name, CLASS)
| | |
| - Param (Name, Value)
| - Layout (Class)
| | |
| - Param (Name, Value)
- Logger (Name, Additive)
| | |
| - Level (Class, Value)
| | | | |
| | - Param (Name, Value)
| - Appender-Ref (REF)
- root
|
- Param (Name, Class)
- Level
| | |
| - Param (Name, Value)
- appender-ref (Ref)
Output format definition:
Message% P output priority% R output from the% m output code Output Self-application starting to output the LOG information consuming the category to which the species belongs to the species, usually the full name% T output of the class generates the log event The thread name% N outputs a carriage return, the Windows platform is "/ r / n", the Unix platform is "/ N"% D output log time point or time, the default format is ISO8601, or after it can be Specify format, such as:% D {YYY MMM DD HH: MM: SS, SSS}, Output Similar: October 18, 2002 22: 28, 921% l Output Log Event location, including category names, The thread that occurs, and the number of rows in the code. It is generally used without using% C.
references:
http://blog.9cbs.net/lxblg/archive/2004/09/14/104207.aspx
http://blog.9cbs.net/baijsp/archive/2004/09/03/log4j.aspx
